Fig. 1: X-ray induced exchange bias reorientation effect.
From: Creating zero-field skyrmions in exchange-biased multilayers through X-ray illumination
a Sketch of using synchrotron X-rays to introduce a uniform exchange bias through scanning a closed area (dashed lines) under a perpendicular magnetic field (H). The magnetic field indicated by the arrow is along the positive direction. b Out-of-plane (red) and in-plane (black) hysteresis loops for the as-grown sample. c Hysteresis loop at 300 K after field cooling process. The field cooling is performed from 400 K and with the field of 1.5 T. Hex indicates the introduced exchange bias in the out-of-plane direction. d Initial magnetic domain pattern imaged by scanning transmission X-ray microscopy (STXM) at zero magnetic field for a sample with structure of Pt (5)/Co (0.6)/IrMn (2)/[Pt (2)/Co (0.6)/IrMn (2)]11/NiO (2) (thickness in nm). e, f Zero-field magnetic domain pattern (6 μm × 6 μm) after scanning the central area (3 × 3 μm2) using a circular X-ray under magnetic fields of 2000 Oe (e) and −2000 Oe (f). The scanning process induces a uniform exchange bias in the scanned area. The exchange bias direction is along the direction of the applied magnetic field. g–i Schematics of the three-quarter sectional cut of the STXM data and the corresponding exchange bias. The arrows in the IrMn layer schematically indicate the antiferromagnetically ordered net magnetization in the out-of-plane direction. The white scale bar in f, i is 1 μm.
